The quantitative relationship between the Bohr sites and the energy of interaction of hemoglobin is being studied. With these data it is possible to refine our model for the action of hemoglobin by assigning proper weights to the contribution of the Bohr effect in generating the cooperativity of hemoglobins. Oxidation of hemoglobin to methemoglobin is being studied under a variety of conditions with different reagents. Cooperative binding systems derived from aggregation and redistribution are under study. The slow generation of amino acids and possibly peptides by solutions of egg albumin and hemoglobin is being studied.